Extended elements and mechanisms for displaying a rich graphical user interface in panel subunit

ABSTRACT

Methods for realizing advanced graphical user interface (GUI) in panel subunit. The present invention provides, in one embodiment, a button GUI element descriptor that defines a bitmap to be displayed when a button is out of focus and another bitmap to be displayed when the button is in focus. In another embodiment, the present invention provides a table GUI element descriptor that defines a table-like on screen display to be displayed on the contoller device. Another embodiment of the present invention provides a panel GUI element descriptor that includes a focused identifier attribute indicating a pre-determined element of the on-screen display as default focus. In this way, the target device would be able to control the default focus of the controller device when displaying an on-screen display. In yet another embodiment, the present invention provides a text GUI element descriptor that includes a font style attribute that dictates whether the text GUI element should be displayed as bold, underlined and/or reversed. By using these extended elements in panel subunit, more complicated and advanced GUI, such as an electronic programming guide (EPG) can be achieved.

This application claims the benefit of U.S. Provisional Application(s)No.: APPLICATION NO.: 60/145,630 FILING DATE Jul. 26, 1999.

This application is a continuation-in-part of and claims the benefit ofapplication Ser. No. 09/108,265 filed on Jul. 1, 1998, now U.S. Pat No.6,148,241, and which designated the U.S.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of consumer electronicdevices. More specifically, the present invention relates to methods andsystems for providing user interfaces for networked electronic devicesincluding remote devices.

2. Related Art

The typical home entertainment system today consists of a variety ofdifferent consumer electronic devices which present and recordaudio/visual media in different ways. In the field of media devices,there is a spectrum of features for products of a given class (VCRs,video camera, etc.). Most of the features are represented by physicalcontrols or elements on a control panel on the device which can bemanipulated by a human user.

Recently, a class of consumer electronic media devices has beenintroduced that can be networked together using a standard communicationprotocol layer (e.g., IEEE 1394 communication standard). The IEEE 1394standard is an international standard for implementing an inexpensivehigh-speed serial bus architecture which supports both asynchronous andisochronous format data transfers. The IEEE 1394 standard provides ahigh-speed serial bus for interconnecting digital devices therebyproviding universal input/output connection. The IEEE 1394 standarddefines a digital interface for applications thereby eliminating theneed for an application to covert digital data to an analog form beforeit is transmitted across the bus. Correspondingly, a receivingapplication will receive digital data from the bus, not analog data andwill therefore not be required to convert analog data to digital form.The IEEE 1394 is ideal for consumer electronics communication in partbecause devices can be added to or removed from the serial bus while thebus is active. If a device is so added or removed, the bus automaticallyreconfigures itself for transmitting data between the then existingdevices. Each device on the bus is a “node” and contains its own addressspace.

The provision of the IEEE 1394 serial communication bus for networkingconsumer electronic devices has introduced a powerful new platform onwhich device functionality and inter-operability can be built. Forinstance, in such a system, complex operations involving mediatransfers, media recordings and media presentation can be performed thatinvolve two or more devices acting in concert. However, interactionbetween these devices can be complex, error prone and laborious if it isrequired that each device be directly touched in order to properlyconfigure the desired operation. The problems associated with properlyconfiguring the media operation can be exacerbated if one or more of thedevices are remotely located and/or need constant attention and oradjustment. What is needed is an effective mechanism for interfacingwith networked consumer electronic devices to facilitate mediaoperations between two or more devices.

In addition, it is often desired to provide remote control access to thefeatures performed by a consumer electronic device so that these devicescan be accessed from a central location within a home or office.However, not all consumer electronic devices are able to provide asophisticated display system for remote interaction, e.g., some devicesoffer only a small liquid crystal display (LCD) or a small collection oflight emitting diodes (LEDs) as display devices. What is needed is amechanism for interfacing remotely with devices that provides asophisticated level of user interaction for many devices. What is neededfurther is a mechanism for interfacing with electronic devices that isflexible and can adapt to new devices and device types within theconsumer electronics market.

SUMMARY OF THE DISCLOSURE

Accordingly, the present invention provides an effective mechanism forinterfacing with networked consumer electronic devices to facilitatemedia operations between two ore more devices. The present inventionalso provides a mechanism for enabling the realization of complicatedgraphical user interfaces (GUIs), e.g., electronic programming guide(EPG), in a controller device. In addition, the present inventionprovides a mechanism whereby the target device can enforce certain“look-and-feel” of the graphical user interface displayed by thecontroller device. Specifically, the present invention provides a numberof extended elements and mechanisms for panel subunit for accomplishingthese goals.

Table GUI Element

The present invention also provides, in one embodiment, a table GUIelement descriptor that defines a table-like on-screen display to bedisplayed on the controller device. Significantly, the table GUI elementdescriptor of the present embodiment enables the target device toenforce a particular arrangement of GUI elements displayed by thecontroller. In addition, the table GUI element descriptor of the presentembodiment allows the target device to indicate particular cells of alarge table to be displayed. In this way, controller devices withlimited capabilities and memory capacities can be used to display alarge amount of information one page at a time. The table GUI elementdescriptor of the present invention further defines the layout of thetable, i.e., the size, the number of columns and rows to be displayed,etc.

Embodiments of the present invention also include a method for realizingcomplex graphical user interface (GUI) in a network having a controllerdevice and a target device. The method includes the steps of: (1) thecontroller device receiving a table GUI element descriptor from thetarget device, wherein the table GUI element descriptor defines a matrixthat includes vertically and horizontally aligned information, andwherein the table GUI element descriptor further defines an on-screendisplay for displaying a portion of the matrix; and (2) the controllerdevice displaying the on-screen display according to the table GUIelement descriptor.

Focused Bitmap

The present invention provides, in another embodiment, a button GUIelement descriptor that defines the appearance of a button element whendisplayed by a controller. Significantly, the button GUI elementdescriptor defines one bitmap to be displayed when the button element isout of focus and another bitmap to be displayed when the button elementis in focus. In this way, the target would be able to control thefocused design of the button.

Embodiments of the present invention include a method for realizingcomplex graphical user interface (GUI) in a system having a controllerdevice and a target device. The method includes the steps of: (1) thecontroller device receiving a button GUI element descriptor from thetarget device, wherein the button GUI element descriptor defines abutton element to be displayed and wherein the button GUI elementdescriptor further defines a first bitmap image to be displayed when thebutton element is out of focus and a second bitmap image to be displayedwhen the button element is in focus; and (2) the controller devicedisplaying said button element as part of an on-screen display, whereinthe controller device displays the first bitmap image when the buttonelement is out of focus and wherein the controller device displays thesecond bitmap image when the button element is in focus.

Default Focus

Another embodiment of the present invention provides a panel GUI elementdescriptor that includes a focused identifier attribute indicating apre-determined element of the on-screen display as default focus. Inthis way, the target device would be able to control the default focusof the controller device when displaying an on-screen display.

Embodiments of the present invention include a method for realizingcomplex graphical user interface (GUI) in a network having a controllerdevice and a target device. The method includes the steps of: (1) thecontroller device receiving a panel GUI element descriptor from thetarget device, wherein the panel GUI element descriptor defines anon-screen display that includes a plurality of elements, and wherein thepanel GUI element descriptor further includes a focused identifierattribute that indicates a pre-determined one of the plurality ofelements as default focus; (2) the controller device displaying theon-screen display according to the panel GUI element descriptor; and (3)the controller device choosing the pre-determined element as focus.

Font Style Attributes for Text Element

Yet another embodiment of the present invention provides a text GUIelement descriptor that includes a font style attribute dictatingwhether the text GUI element should be displayed as bold, underlinedand/or reversed. In this way, the target device would be able toexercise more control over the “look-and-feel” of the GUI as displayedby the controller device such that more sophisticated GUIs can berealized.

Embodiments of the present invention also include a method for realizingcomplex graphical user interface (GUI) in a network having a controllerdevice and a target device, the method comprising steps of: (1) thecontroller device receiving from a text GUI element descriptor from thetarget device, wherein the text GUI element descriptor defines a textelement to be displayed and wherein the text GUI element descriptorfurther includes a font style attribute; and (2) the controller devicedisplaying the text element according to the font style attribute.

Panel Subunit

Embodiments of the present invention are implemented within a network ofelectronic devices, e.g., digital television (DTV), set-top box (STB),video cassette recorder, compact disk device, personal computer systems,etc., that are coupled together using a standard communication protocollayer, e.g., the IEEE 1394 serial communication standard. The presentinvention utilizes a panel subunit to allow any compliant device (e.g.,a target device) to describe the physical appearance of its controls anddisplays (e.g., elements) to another device (e.g., an intelligentcontroller) and allows the intelligent controller to trigger actions onthe target device as if a user had physically manipulated the controlson the target device directly. An intelligent controller (e.g., a TV orset-top-box or both) monitors the network to discover the units coupledthereto and is programmed to locate panel subunits that are defined fora target device. The target device may be remotely located.

In general, the panel subunit then provides the intelligent controllerwith information for rendering a depiction of the controls and displaysof the target device and this depiction can be interacted with by a userfor remotely triggering actions by the target device. The panel subunitis defined such that command interpretations and image alterations arecontrolled by the target device thereby reducing the responsibility ofthe intelligent controller in managing the user interface with genericuser events.

The panel subunit uses control objects stored in an object descriptorlist to define the physical controls of the target device. The controlobjects are defined with several standard types of controls and displays(e.g., push buttons, sliders, dials, LCD screens, etc.) that arecommonly found on consumer electronic devices. The control types havewell defined behaviors (e.g., buttons are pushed, dials are moved,values are input, etc.). In addition, the panel subunit defines a set ofcommands which are to be applied to any of these controls when selectedby the user. The commands are defined to be sufficiently generic so thatthey apply to most types of controls. The panel subunit also definesgeneric user interaction commands (or user events) which can be appliedto the controls (e.g., press, press and hold, release, input value,etc.) by a user. The purpose of these generic user events is toencapsulate the typical user manipulated action for the controls and tolet the target device decide the manner in which to interpret the useractions on its own thereby relieving the intelligent controller of theseresponsibilities.

A status descriptor of the panel subunit keeps the intelligentcontroller informed of the status of the target device beingmanipulated. The status descriptor data structure is dynamic and ismaintained up to date by the panel subunit. The intelligent controllerexamines the status descriptor to update its graphical display toindicate the target device status to the user. A panel statusnotification command allows the intelligent controller to post anotification request to the target device to indicate when any changesin the state of the target device result in a change in the statusdescriptor. Related controls of a target device can be grouped togetherinto local groups which the panel subunit allows to be displayed orprocessed together in special ways.

BRIEF DESCRIPTION THE DRAWINGS

FIG. 1 illustrates an exemplary networked system of electronic devicesincluding a video camera, a video cassette recorder, a computer, aset-top-box, a television and a compact disk changer.

FIG. 2 illustrates components of an intelligent controller in accordancewith the present invention.

FIG. 3A is a perspective view of a target device having panel displayelements and panel control elements.

FIG. 3B is a perspective view of the target device of FIG. 3A having afront panel in the flipped-open state to expose more control and displayelements.

FIG. 4 illustrates a logical block diagram of the subunits locatedwithin a target device (a VCR) including the panel subunit of thepresent invention.

FIG. 5 illustrates descriptor information of a panel subunit inaccordance with the present invention including a subunit identifierdescriptor, panel lists and objects of control objects.

FIG. 6 illustrates the contents of the general list informationstructure including a group identification structure in accordance withthe panel subunit of the present invention.

FIG. 7A and FIG. 7B illustrate exemplary control object descriptors inaccordance with the panel subunit of the present invention.

FIG. 8 illustrates a panel subunit status descriptor data structure inaccordance with the present invention.

FIG. 9 is a flow diagram of steps performed by an intelligent controllerin accordance with the present invention for generating a userinterface.

FIG. 10 illustrates an exemplary user interface displayed by the presentinvention based on a panel subunit and representing an on-screenkeyboard.

FIG. 11 illustrates exemplary panel subunit descriptor information forgenerating the on-screen keyboard example of FIG. 10 in accordance withthe present invention.

FIG. 12 illustrates exemplary steps and communications between anintelligent controller and a remote target device in accordance with thepanel subunit of the present invention.

FIG. 13 illustrates an exemplary network of electronic devices in whichembodiments of the present invention may be practiced.

FIG. 14 is a depiction of an exemplary electronic program guide (EPG)displayed by a controller device in accordance with an embodiment of thepresent invention.

FIG. 15 illustrates a particular implementation of a table GUI elementdescriptor in accordance with one embodiment of the present invention.

FIGS. 16A, 16B, 16C and 16D represent data flow between a controller anda target for generating table graphical user interface with a table GUIelement descriptor in accordance with one embodiment of the presentinvention.

FIGS. 17A and 17B depict exemplary EPG tables displayed by a controllerdevice in accordance with an embodiment of the present invention.

FIG. 18 illustrates a flow diagram of steps performed within anelectronic network for constructing an EPG table using a table GUIelement extension to panel subunit according to one embodiment of thepresent invention.

FIG. 19 illustrates a particular implementation of a button GUI elementdescriptor.

FIGS. 20A and 20B depict an exemplary panel subunit as displayed by acontroller using button GUI element descriptors of the presentembodiment.

FIG. 21 illustrates a particular implementation of a panel GUI elementdescriptor in accordance with one embodiment of the present invention.

FIGS. 2A and 22B illustrate data flow between a controller and a targetof a network using the panel GUI element descriptor of the presentembodiment.

FIG. 23 illustrates a particular implementation of a text GUI elementdescriptor according to one embodiment of the present invention.

FIG. 24 is a depiction of an exemplary electronic program guide (EPG)displayed by controller device in accordance with an embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following detailed description of the present invention, commandpass through mechanism for use with a panel subunit for remotelyinterfacing with a target device via an intelligent controller within anetwork of consumer electronic devices, numerous specific details areset forth in order to provide a thorough understanding of the presentinvention. However, it will be recognized by one skilled in the art thatthe present invention may be practiced without these specific details orwith equivalents thereof. In other instances, well known methods,procedures, components, and circuits have not been described in detailas not to unnecessarily obscure aspects of the present invention.

Embodiments of the present invention are drawn to a panel subunit thatallows any compliant device (e.g., “target device”) to describe itsphysical appearance including controls and displays, etc., to an outsideintelligent controller device. The target device can be remote to theintelligent controller. The intelligent controller then generates a userinterface for the target device including: 1) interactive controls; and2) user display information pertinent to the target device. The panelsubunit allows the intelligent controller to trigger actions on thetarget device as if a user had physically manipulated the controls ofthe target device. The intelligent controller and the target device areconnected to the same communication network (e.g., using the IEEE 1394serial standard). The present invention can also be used in oneembodiment to promote high levels of inter-operability between any ofthe devices which support the well known AV/C command and controlprotocol.

Generally, the present invention allows an intelligent controller tocommunicate with the panel subunit of the target device and inquireabout the various types of controls which it has, e.g., buttons,sliders, etc. The intelligent controller then generates, on its display,a human interface based on these control object descriptions, and whenthe user manipulates this human interface, the controller sends specialuser events to the target device. The information that is capable ofbeing displayed by the intelligent controller can be made scaleable bythe target device so that the human interface displayed can adapt to theparticular display capabilities of the intelligent controller device.The intelligent controller monitors the target device to maintain themost current status presented to the user.

Thus, the intelligent controller does not need to have advance knowledgeof any specific features in the target device or how they are used orinvoked because this functionality is the responsibility of the targetdevice. All issues such as state transitions and inter-controldependencies are handled automatically the by target deviceindependently of the intelligent controller responsibility. The presentinvention removes all requirements for items such as state transitiontables and their execution environment, because it takes advantage ofthe functionality that is already built into a media device and used tohandle the physical buttons as they are manipulated by the user. Forinstance, when the intelligent controller asks the target to “simulatethe press of button 5,” the intelligent controller does not need to haveany knowledge at all about what is happening within the target deviceupon being notified of the user action. The state transition logic forwhat happens when “button 5” is pressed is all contained within thetarget device. This is advantageous because it enhances theinter-operability between the intelligent controller and the targetdevice while at the same time greatly reduces the responsibilities ofeach.

In addition to describing physical controls and appearances, the presentinvention can be used to describe logical controls and appearances ofelements of a logical control panel. For instance, a logical controlpanel can be used to control a “black box” not having any physicalcontrols but having only a 1394 connector with the black box beinglocated in a closet or other remote location. In this case, the blackbox is manipulated with on screen controls via its panel subunit therebyhaving no physical control panel itself.

Network Environment of the Present Invention

FIG. 1 illustrates an exemplary network system 5 that can support theembodiments of the panel subunit of the present invention. Exemplarysystem 5 includes consumer electronic devices (including computersystems) as nodes but could be extended equally well to cover otherelectronic devices. System 5 includes a video camera 10, a videocassette recorder (VCR) 12, a computer system 14, a set-top-box (STB)13, a television set (TV) 11 and a compact disk (CD) changer 20connected together with the network by IEEE 1394-1995 (IEEE 1394) cables15, 16, 18 and 19. It is appreciated that the panel subunit embodimentsof the present invention are equally well suited for application withany bus structure and the IEEE 1394 bus structure is shown and describedherein as an example bus architecture only. The STB 13 can be coupled toreceive media from a cable TV system. The IEEE 1394 cable 16 couples thevideo camera 10 to the VCR 12 allowing the video camera 10 to send data,commands and parameters to the VCR 12 for recording (or to any otherdevice of the network 5). The IEEE 1394 cable 18 couples the VCR 12 tothe computer system 14 allowing the VCR 12 to send data, commands andparameters to the computer system 14 for display (or to any other deviceof the network 5).

The IEEE 1394 cable 15 couples the STB 13 to the computer system 14. TheSTB 13 is also coupled to the TV 11 by the cable 17. The CD changer 20is coupled to the computer system 14 by the IEEE 1394 cable 19. Theconfiguration 5 illustrated in FIG. 1 is exemplary only and it should beapparent that an audio/video network in accordance with the presentinvention could include many different combinations of components. Thedevices within an IEEE 1394 network 5 are autonomous devices, meaningthat in an IEEE 1394 network, in which a computer is one of the devices,there is no true master-slave relationship between the computer system14 and the other devices. In fact, as described below in an exemplaryembodiment of the panel subunit of the present invention, theintelligent controller is the STB 13. In many IEEE 1394 networkconfigurations, a computer system 14 may not be present. Even in suchconfigurations, the devices within the network are fully capable ofinteracting with each other on a peer-to-peer basis. It should berecognized that data, commands and parameters can be sent between all ofthe devices within the IEEE 1394 network 5.

The IEEE 1394 serial bus used by system 5 of FIG. 1 is a high-speed busarchitecture for interconnecting digital devices thereby providing auniversal input/output connection. The IEEE 1394 standard defines adigital interface for the applications thereby eliminating the need foran application to covert digital data to analog data before it istransmitted across the bus. Correspondingly, a receiving applicationreceives digital data from the bus, not analog data, and therefore isnot required to covert analog data to digital data. The cable requiredby the IEEE 1394 standard is very thin in size compared to other bulkiercables used to connect such devices. Devices can be added and removedfrom an IEEE 1394 bus while the bus is active. If a device is so addedor removed, the bus automatically reconfigures itself for transmittingdata between the then existing nodes. A node is considered a logicalentity having a unique address on the bus structure. Each node providesan identification ROM, a standardized set of control registers and itsown address space.

The IEEE 1394 communication standard within system 5 of FIG. 1 supportsisochronous data transfers of digital encoded information. Isochronousdata transfers are real-time transfers which take place such that thetime intervals between significant instances have the same duration atboth the transmitting and receiving applications. Each packet of datatransferred isochronously is transferred in its own time period. Anexample of an application for the transfer of data isochronously is froma VCR 12 to TV 11 of FIG. 1. The VCR 12 records images and sounds andsaves the data in discrete packets. The VCR 12 then transfers eachpacket, representing the images and sounds recorded over a limited timeperiod, during that time period, for display by the TV 11. The IEEE 1394standard bus architecture provides multiple channels for isochronousdata transfers between applications. Specifically, a six bit channelnumber is broadcast with the data to ensure reception by the appropriateapplication. This allows multiple applications to simultaneouslytransmit isochronous data across the bus structure. Asynchronoustransfers are traditional data transfer operations which take place assoon as possible and transfer an amount of data from a source to adestination.

Intelligent Controller

User interface aspects of the panel subunit of the present invention areimplemented within an intelligent controller device. The intelligentcontroller can be any device coupled within a networked system (e.g.,system 5 of FIG. 1) designated by the user and having certain basicinput functionality and basic display capability. In one embodiment ofthe present invention, the STB 13 and the TV 11 act as the intelligentcontroller. In other embodiments, the computer system 14 can act as theintelligent controller or the TV 11 can act alone as an intelligentcontroller. Any device having “display” and input capability can act asthe intelligent controller, e.g., a personal digital assistant (PDA), ahand-held electronic device, a cell phone, etc.). Within the context ofthe present invention, the intelligent controller is the device thatprovides a user interface for controlling events on another, remote,target device within the network 5. To this extent, the intelligentcontroller communicates with a display device and an information inputdevice. The display and input capabilities of the intelligent controllerdevice define the type of user interface that the intelligent controllercan provide to a user and the panel subunit of the present inventionallows the definition of scaleable user interface capabilities.

FIG. 2 illustrates the components of the intelligent controller, and inthis example it is the STB 13. STB 13 includes an address/data bus 100for communicating information, a central processor 101 coupled with thebus 100 for processing information and instructions, a volatile memory102 (e.g., random access memory RAM) coupled with the bus 100 forstoring information and instructions for the central processor 101 and anon-volatile memory 103 (e.g., read only memory ROM) coupled with thebus 100 for storing static information and instructions for theprocessor 101. STB 13 can also optionally include a data storage device104 (“disk subsystem”) such as a magnetic or optical disk and disk drivecoupled with the bus 100 for storing information and instructions. Inone embodiment, the display device 105 can be part of the intelligentcontroller. As shown in FIG. 2, the display device (e.g.,. TV 11) isexternal to the STB 13. When incorporated into the intelligentcontroller, the display device 105 can be a display screen (e.g., flatpanel or CRT, etc.) or it can be a liquid crystal display (LCD) panel orother suitable display device for the display of alphanumeric and/orgraphic information.

The intelligent controller 13 also interfaces with or includes one ormore user input devices. In one embodiment, the input device can be analphanumeric input device 106 including alphanumeric and function keyscoupled to the bus 100 for communicating information and commandselections to the central processor 101. Alternatively, or in addition,the intelligent controller 13 can interface with or include a cursorcontrol or cursor directing device 107 coupled to the bus forcommunicating user input information and command selections to thecentral processor 101. The cursor directing device 107 can beimplemented using a number of well known devices such as a mouse, atrack ball, a track pad, an electronic pad and stylus, an opticaltracking device, a touch screen etc. In addition, the user input devicecan also be a remote control device, e.g., a universal remote controldevice having a number of buttons, dials, etc., with an infra-red signalcommunication capability. STB 13 can also include a signal generatingdevice 108 coupled to the bus 100 for interfacing with other networkeddevices over the IEEE 1394 bus.

The target device of the present invention can also include one or morecomponents as described with respect to FIG. 2. Particularly, the targetdevice in accordance with the present invention includes computerreadable memory units which can include one or more ROM and/or RAM unitsfor storing panel subunit information of the present invention which aredescribed below.

Panel Subunit of the Present Invention

The present invention defines a subunit type called a “panel” subunit.The panel subunit is defined for a target device and outlinescharacteristics for generating a user interface on an intelligentcontroller device (e.g., STB 13) of a network system 5. The panelsubunits can be defined for multiple target devices and therefore manypanel subunits can be included within a network system 5. For aparticular target device, its panel subunit can be stored as a datastructure within computer readable memory units of the particular targetdevice.

FIG. 3A illustrates a perspective view of the VCR 12 of FIG. 1 as anexemplary target device. Although, generally, any electronic device canhave its own panel subunit and thereby be a “target device,” thefollowing discussion illustrates an exemplary case where the VCR 12 isthe target device. VCR 12 contains a video tape slot 212 for insertionand removal of video tape media. The VCR 12 also contains one or moreliquid crystal displays (LCDs) 214.

FIG. 3B illustrates the VCR 12 with a control panel 220 flipped-downexposing certain controls and further displays (e.g., “elements”). Thecontrol panel 220 contains another LCD display 240 and includes ascrubber control 230 or “dial.” The control panel 220 also containscertain tape transport controls 250 (including play, pause, stop,rewind, fast-forward, buttons etc.). When the control panel 220 isflipped down, it exposes tuner preset buttons 225. In the presentinvention, devices can have more than one logical control panel. In thisconfiguration, the VCR 12 has two logical subpanels. The first subpanelincludes the controls and display of the flip-down control panel 220 andthe second subpanel includes the tape slot 212 and the tuner presetbuttons 225. Another subpanel could define the LCD panel 214.

FIG. 4 illustrates a logical block diagram of some of the subunits thatcan be associated with VCR 12 in accordance with the present invention.Within the well known AV/C protocol, subunits are logical, not physical,groupings of functionality that can be individually addressed andcontrolled within a device. For example, a VCR device 12 can have twosubunits, one subunit 312 for the actual VCR tape transport mechanism,and another subunit 320 for the tuning functionality. The panel subunit314 of the present invention adds a novel logical subunit that can beassociated with the VCR device 12. As described further below, the panelsubunit 314 of the present invention is realized, in one embodiment, asone or more data structures stored in computer readable memory units ofthe target device e.g., the VCR unit 12. It is possible for a panelsubunit for a first device (e.g., of limited memory capacity) to existon a second device (having more memory), whereby the second device actsas a proxy for the first device's panel subunit.

The panel subunit 314 is a collection of data structures called“descriptors” that describe the physical controls on the target device(e.g., the control panel). In operation, the intelligent controller(e.g., STB 13) accesses the panel subunit 314 of the target device, andbased thereon, implements a user interface for using the target device(e.g., the VCR 12). The user interface involves the display (e.g., TV11) and user input devices associated with the intelligent controller,as described with respect to FIG. 2. The specification for the panelsubunit 314 defines several standard types of controls and displays thatare commonly found on consumer electronic devices, such as push buttons,sliders, dials, LCD screens, etc. As an example, the descriptions withinthe panel subunit 314 for VCR 12 could represent the buttons, dial andLCD screens of FIG. 3A and FIG. 3B.

The control types defined by the panel subunit 314 have well definedbehaviors. For instance, buttons are pushed and released and typicallyhave two values, sliders may have several discrete values or acontinuous range of values. Further, some standard control types may becombined within the descriptors to form hybrid or custom controls. Oneexample of this is a dial with a push button in the middle or a buttonwith an LED in the middle. Such composite control mechanisms aresupported by the panel subunit of the present invention. Finally, vendorspecific custom controls may also be defined.

In addition to standard control types, the panel subunit 314 of thepresent invention also defines a set of commands which may be applied toany of these controls. The commands are defined to be sufficientlygeneric so that they apply to most types of controls. For example,issuing the command SET CONTROL VALUE (control 1, 6) by the intelligentcontroller may cause a volume slider to be set to the value 6,representing a change in volume. Likewise, the same command type withdifferent operands can be issued as SET CONTROL VALUE (control 5,“please enter the track name”), and it would cause that text to showupon the LCD display of a MiniDisc recorder 20, prompting the user toenter a name for a track on the disc. Further, within the panel subunit,some commands can be specific to certain kinds of controls.

The panel subunit 314 also defines “user interaction commands” or userevents which can be applied to the controls of the user interface. Thepurpose of these generic user events is to encapsulate the typical usermanipulation actions for controls, and to let the target deviceinterpret what it means when these user events occur thereby freeing theintelligent controller of this responsibility. For example, many CDplayers 20 have multiple semantic meanings for the fast forward buttonon the device and these meanings are affected by the current state ofthe device. Consider the following:

TABLE I Current Device Setting Action Result Device Is Not Playing FFButton Pressed Advance to the Next Track and Hold Device Is Playing FFButton Pressed Advance to the Next Track and Continue Playing from thatPoint Device Is Playing FF Button Pressed Play in “Fast Forward” Modeand Held Down

As shown above, the actions taken by the target device vary based on itscurrent state and what the user does with the physical controls. Thepanel subunit of the present invention defines several user actioncommands such as “PUSH,” “PRESS AND HOLD,” and “RELEASE” that aretriggered by user interaction with the displayed user interface. Inaccordance with the present invention, the intelligent controller of thepresent invention has no notion of what the target device will do inresponse to the commands that are issued to it. All concerns regardingthe state transition as shown in the Table I are handled inside of thetarget device. It is appreciated that the target device already needs tohave this logic in place in order to process the user interaction on itsphysical control panel. The panel subunit of the present invention isviewed as another mechanism by which to access these logical entrypoints.

It is important that the intelligent controller always keep the userinformed regarding the status of the target device being controlled. Inone embodiment, it is possible that the intelligent controller and theuser are sitting in one room of a house or business office and thetarget device is located in another room or office. Because theintelligent controller has no pre-defined knowledge of how to interpretthe user interaction elements, it needs to have a mechanism of keepingits display updated with the most current status of the target device.It does this by making use of the status reporting mechanism that hasbeen defined for the AV/C protocol, in one embodiment, using a statusdescriptor data structure and a panel status notification command inaccordance with the present invention.

The status descriptor data structure is a dynamic data structure that isalways kept up-to-date by the panel subunit 314 of the presentinvention. The intelligent controller can examine this structure at anytime so that it can update its graphical display to indicate the targetdevice status to the user. The panel status notification command of thepresent invention allows the intelligent controller to post anotification request to the target device. When any change in the stateof the device results in a change to the status descriptor datastructure, then the target device sends a notification to theintelligent controller. The intelligent controller then updates itsgraphical display as appropriate in response to the status information.

The AV/C protocol allows a device (also called a unit herein) to containany number of subunits of the same type. Therefore, a device can havemore than one panel subunit of the present invention. For instance, onepanel subunit can be defined for the front panel of FIG. 3B and anotherpanel subunit can be defined for the flip-down panel 220. Other panelsubunits can be defined for the side and back panels, if any.Alternatively, a single panel subunit can be defined to encompassseveral controls as shown in FIG. 5. In this approach, a single panelsubunit can contain any number of control lists which are hierarchicallyordered. Each control list of the present invention represents a controlpanel of the target device. All of these lists are accessed via thesingle panel subunit 314.

Part of the panel subunit data structures includes geometry informationdescribing the layout image and orientation of panels and controls sothat they can be represented to the user in a manner similar to theirphysical appearance on the target device or in a manner “suggested” bythe target device. As standard controls can be combined into hybridcontrols, this geometry information can also be defined to indicate thepresence of panel hierarchies, such as panels hidden behind a frontflip-down face 220 (FIG. 3B). This is commonly found in many VCR deviceswhere some basic controls are on the face of the VCR device and the moreadvanced controls and features are hidden behind the flip-down frontpanel 220.

Panel Description of the Panel Subunit

FIG. 5 illustrates data descriptor information maintained by computerreadable memory units of a target device, e.g., VCR 12. It isappreciated that the data descriptor data structures found in FIGS. 5-8and 11 are all maintained and realized within computer readable memoryunits of the target device in accordance with the present invention. Thepanel subunit 314 (FIG. 4) includes a panel subunit identifierdescriptor data structure 340. The identifier descriptor list 340indicates identifiers for each of the main panel lists supported by thepanel subunit 314. Each of these panel lists can contain a controlobject which has a child list, indicating a panel hierarchy. Forinstance, primary identifier list 340 relates to the front panel for thetarget device and includes an identifier (e.g., pointer) 342 whichpoints to a secondary identifier structure 350 which itself includes twosub-panel descriptions (e.g., one for the face of the VCR 12 and one forthe flip-down panel 220). The primary identifier 340 also includes anidentifier (e.g., pointer) 344 for another secondary identifier list 390describing a rear panel for the target device. In this manner, the mainidentifier and the secondary identifier structures of the panel subunit314 can define hierarchical relationships between the descriptor listinformation and thereby between the panels and sub-panels themselves.

The secondary identifier descriptor list 350 of FIG. 5 is a descriptorlist including a general list information field 352 and one objectcontrol descriptor 354 for describing the LCD display 214 (FIG. 3A). Adescriptor list within the present invention can include object controldescriptors, general information, and pointers to child descriptorlists. Therefore, a control object within a descriptor list can point toanother descriptor list indicating a parent-child relationship betweenthe control object and the indicated descriptor list. Descriptor list350 includes a pointer 356 indicating a child descriptor list 356 a usedto describe “sub-panel1” which is a portion of the controls of the frontpanel for VCR 12 in this example. Further, descriptor list 350 includesa pointer 358 indicating a child descriptor list 358 a used to describe“sub-panel2” which is another portion of the controls of the front panelfor VCR 12. In this example, the descriptor list 356 a for sub-panel1defines the controls on the face of VCR 12, e.g., buttons 225 for thetuner subunit 320. The descriptor list 358 a for sub-panel2 defines thecontrols on the flip-down control 220 of VCR 12, e.g., buttons 250,display 240, and dial 230.

As with any descriptor list data structure, descriptor lists 356 a and358 a each contain a respective general list information field 360 andfield 380 and also contain respective lists of control objects. Inaccordance with the present invention, a list which contains controlobjects for a panel is used to describe the control panel itself, aswell as to hold the collection of objects. Generally, information thatdescribes the collection (the panel description) would contain thefollowing: (1) panel identifier (e.g., front, back, left side, etc.);(2) panel layout geometry (e.g., size of panel, orientation of controls,definition of groups, etc.); (3) group descriptions for each group ofcontrols where the following can be defined, group label, group boundingbox/position within the panel, and other group related information; and(4) a name for the panel subunit. An example is shown in FIG. 6.

FIG. 6 illustrates the information included within the general listinformation data structure 380 of the secondary descriptor list 358 afor the front sub-panel1 of the target device. Secondary descriptor list358 a contains general list information 380 and a collection of nobjects 382 to 386. Exemplary data structure 380 includes fields410-420. Field 410 indicates the hierarchical position or identifier forthe descriptor list 358 a in which the field is included. For instance,field 410 indicates which physical panel the information represented,e.g., whether this descriptor list 358 a represents a front, side, rear,etc., control panel. In this example, descriptor list 358 a is a “front”panel. Field 412 defines the opening or access options used to obtainaccess to the control panel for which descriptor list 358 a is defined,e.g., flip-down, flip-up, flip-out, left, right, direct access, etc. Inthis case, control panel 220 (FIG. 3B) has “flip-down” style access.Field 414 defines the general size and shape of the control panel forwhich descriptor list 358 a is defined (e.g., rectangle, circular,oblong, triangle, polygon, etc.). In this case, control panel 220 isrectangular in shape.

Fields 416-420 of FIG. 6 are used to define groups within the controlpanel for which descriptor list 358 a is defined. Groups can be used toseparate certain control features that are similar or control a similarfunction or feature. For instance, buttons that each relate to thecontrol of the tape mechanism for a VCR 12 can be assigned into onegroup while buttons that control the channel selection or the volumeselection of the VCR 12 can be assigned in a separate group. Groups havespecial functions within the present invention, e.g., they can bedisplayed spatially together on the display of the intelligentcontroller, and can have other defined attributes in common. Field 416indicates the number of groups defined for descriptor list datastructure 358 a and fields 418-420 represent the group descriptioninformation for a number of exemplary groups.

FIG. 6 illustrates fields 430-438 which represent an exemplary groupdescription that is contained in field 420 for an exemplary group (n−1).Information field 430 includes the number of control objects that aredefined for this group. Field 432 includes a group identification numberor string that is unique for this group and used to identify the groupby control objects. Each control object that is to be included in thedefined group includes the identifier 432 in its object description(described below). Field 436 indicates the spatial boundary box in whichthis group is included for the control panel. This information indicateswhere this group exists with respect to other defined groups in the userinterface layout and is used for rendering the image of the controlpanel on the display of the intelligent controller. Field 438 is a grouplabel that can be used to provide access to and represent the controlobjects of this group for cases where the display unit of theintelligent controller is not sophisticated enough to provide images orfurther information. Field 438 typically contains a string or other textlabel that can be used, in one embodiment, as a tab index in atabbed-panel presentation of information. In a tabbed-panelpresentation, all the defined tabs for all groups are displayed alongthe side of the display and groups are selected for presentation byselecting one tab or another.

FIG. 7A illustrates the data of a control object 382 in accordance withthe panel subunit of the present invention. Exemplary control object 382is included within descriptor list data structure 358 a. In oneembodiment, the panel subunit of the present invention presents itsinformation to controllers via the AV/C object and object list datastructures. These data structures are generic containers whose contentsare specialized based on the owner of the structure. A panel subunit ofthe present invention contains a list of its controls (e.g., listdescriptor 358 a), with each control being represented by a controlobject in the list. Within the present invention control objects can bedefined to represent user input devices (e.g., buttons, sliders, toggleswitches, etc.) and an also be defined to represent information displays(e.g., LCD panels, dials, etc.).

FIG. 7A illustrates the information of a control object 382 representinghe LCD panel 214 of FIG. 3A. Field 440 describes the type of controlobject being defined. In this case it is “LCD Panel” type. Other controltypes for displaying information include “Display,” “Dial,” “CRTDisplay,” “LED” and “Alpha/Numeric Display.” Other control types forinformation input devices include “Button,” “Slider,” “Rotator,” “ToggleSwitch” and “Rocker Switch.” Field 442 includes a graphical image of thecontrol object. This image information is typically raster data (e.g.,bit mapped) and may include color and other attribute data. In thisparticular instance, the control image 442 a is in the shape andcharacter of the outline of an LCD display to represent LCD panel 214.Field 442 could also contain a collection of images used for performinganimation in a predefined sequence of presentation. Field 444 representsthe dimensions of the image 442 a and in one embodiment is representedin screen coordinates (x, y). To generalize these coordinates forapplication with many screen dimensions, the (x, y) values can berepresented in relative terms with respect to the left corner, e.g., the(0, 0) coordinate position, of the display screen.

Field 446 of FIG. 7A represents the group identification or name withwhich this control object 382 is associated. Controls can be clusteredinto groups based on layout information defined by the panel subunit ofthe present invention. This field 446 is optional as an object does notnecessarily need to be associated with any group at all. If a group isassociated with this control object 382, then field 448 represents therelative position 448 a within the group boundary 448 b in which thiscontrol object 382 belongs. This information can be expressed incoordinate values. Field 450 represents the allowable or valid valueranges that can be taken by this control object in response to a userevent. This field 450 can also include a data type indicator (e.g.,16-bit representing integer, floating point, etc.) In the case of adisplay object, field 450 represents the character or icon sets that canbe displayed within the control object. In the case of a user inputcontrol object, field 450 indicates the range of possible values thatcan be set by this control object. If the control object was a slider,then a range of values is appropriate. If the control object is a buttonor toggle switch, then possibly only two states (e.g., 0 or 1) are validfor the control object.

Field 452 of FIG. 7A is optional and represents the equivalent AV/Ccommand that occurs when the control object 382 is activated. This AV/Ccommand can be communicated by the intelligent controller over thenetwork within system 5 when the control object 382 is invoked. Field452 is optional because the target device has the capacity to interpretchanges in the control object as communicated to it by the intelligentcontroller without the need for a communicated AV/C command. The panelsubunit 314 represents the VCR 12 in this example. The manipulation ofthose controls may cause a state change in other subunits within thetarget device. The values of field 454 represents which subunit (subunittype and ID) can be effected by this control object. Field 454 islikewise an optional field that indicates the identification of thetarget device associated with the control object. Again, thisinformation is optionally included within the control object 382 but ismaintained by the intelligent controller by virtue of which targetobject contained the panel subunit in the first instance.

Field 456 is an identifier or name string that can be associated withthe control object. In instances where the display device of theintelligent controller is not sophisticated, field 456 can be used to atleast provide a basic textual description of the control object which ispresented for user interface functionality. Field 458 contains a helpstring that can be displayed on the display of the intelligentcontroller if a help feature is employed by the user. The help stringdescribes what the control object does. This can be extended to providea help string for each state of the control object. The help string canidentify the control object and give tips on how to use the controlobject, its purpose and expected functionality and value range.

FIG. 7B illustrates information associated with an exemplary controlobject 384 for one of the push buttons of buttons 250 of the flip-downpanel 220 of FIG. 3B. In this example, the “Play” button is beingrepresented for VCR 12. Field 460 defines the control object as a“button” control type. Field 462 can contain multiple images or “icons”that can be used for displaying the control object. The icons can, forinstance, represent different states of the control object, e.g., suchas a button which is highlighted differently whether it is pressed orreleased. Field 462, in this case, contains a number of icons thatrepresent the image of the button in different states (e.g., pressed orreleased). Image 462 a represents the image for the button pressed andimage 462 b represents the image of the button for the button released.Field 464 represents the screen dimensions of the images of field 462and field 466 represents a group identification, if any, for controlobject 384. In this case, all of the buttons 250 (FIG. 3B) are clusteredtogether into a single group because they control the tape mechanism forVCR 12, e.g., Group Identification=“Tape Mechanism,” where this groupwould have to have been previously defined in a data structure of FIG.6.

Field 468 represents the relative position 468 a of the control object384 within the group boundary 468 b. In this case, the control object384 represents the third button from the left within the collection ofbuttons 250. Field 470 represents the possible range of values can berepresented by the button, e.g., in this case 0 to 1, and the value isan integer. If the control object was a slider, then a possible range ofvalues (e.g., 0 to 10) could be represented with the values beinginteger or floating point type.

Optional field 472 represents the equivalent AV/C command for “Play” andcan be communicated by the intelligent controller when control object384 is pushed. When a user event such as PRESS is issued, it may resultin the same action as if a standard AV/C command, such as the VCRsubunit PLAY command, had been issued. The value of field 472 is theopcode of the equivalent AVIC command. Optional field 474 represents thenetwork identification for the target device (in this case, the VCRsubunit). Field 476 is an identifier or name string that can beassociated with the control object, e.g., “Play.” In instances where thedisplay device of the intelligent controller is not sophisticated, field476 can be used to at least provide a textual description of the controlobject which is presented for user interface functionality. Field 478contains a help string that can be displayed on the display of theintelligent controller if a help feature is employed by the user, e.g.,“Press Play to Start Watching A Tape in the VCR.” The help string couldalso describe why the control object is in a particular state, e.g.,“The Play Button is Disabled Because There is No Tape in the VCR.”

It is appreciated that the control objects of FIG. 7A and FIG. 7B areexemplary only and that other similar control object descriptions can beused to realize a user interface for all user inputs and user displaysof the VCR 12 for all control panels. It is further appreciated thateach other control object of FIG. 5 can analogously be defined inaccordance with the present invention.

FIG. 8 illustrates a panel subunit status descriptor 500. The panelsubunit 314 of the present invention also includes a panel subunitstatus descriptor 500 data structure. The status descriptor 500 is adata structure maintained in computer readable memory units of thetarget device and represents the current state of all control objectsdefined for a particular panel subunit in accordance with the presentinvention. The information maintained in the status descriptor 500 isdynamic, and is kept up-to-date by the panel subunit 314 of the presentinvention. Within the status descriptor 500, a separate control statusfield is maintained for each defined control object. When changes occurto the status descriptor 500, a notification can be forwarded to anyintelligent controller that previously indicated that it was to benotified of any changes. The overall status descriptor 500 contains twomain areas, one area 510 contains general status information for thepanel subunit and a separate area 512 is defined for each of the controllist hierarchies. Within each of these control list areas are statusinformation for each control. Status information includes the currentstate of the control object (e.g., the button is currently pressed) andthe current value of the control object (e.g., the LCD panel iscurrently displaying the text “Enter Track Name.”).

In operation, an intelligent controller can request notification forindividual control lists or for the general area of the panel statusdescriptor 500. When the status of one of these areas changes, theintelligent controller is notified. If status for an area changes forwhich an intelligent controller had not requested notification, theintelligent controller is not notified. This operation allows thevarious controllers and target devices to optimize the use of the systemnetwork bandwidth by not sending out unnecessary messages.

Status descriptor 500 of FIG. 8 is shown as an example and includes aprimary status list 505 which includes a general information field 510for panel subunit 314 and pointers 512 and 514 to other major statuslists. Pointer 512 points to status list 535 for representing the statusof the front panel. Status list 535 includes a status field for eachcontrol object defined for the front panel. Pointer 514 points to thestatus list 516 for an exemplary left side panel. Field 518 of statuslist 535 indicates general status information for any control objectsdefined with respect to the front panel including whether or not thepanel is open, closed, etc. Field 520 represents the current state/valueof control object 0 defined for the front panel. Likewise, field 522represents the current state/value of control object 1 defined for thefront panel.

Field 526 is a pointer to the control list 530 indicating thestates/values for the control objects defined with respect to thesub-panel1 of the front panel.

These control objects are defined with respect to descriptor list 356 a(FIG. 5). Within status list 530, a separate control status field isdefined for each control object. Field 528 of control list 535 is apointer to the control list 532 indicating the states/values for thecontrol objects defined with respect to the sub-panel2 of the frontpanel. These control objects are defined with respect to descriptor list358 a (FIG. 5). Within status list 532, a separate control status fieldis defined for each control object.

FIG. 9 is a flow diagram illustrating steps of a process 700 implementedin accordance with the panel subunit of the present invention.

Process 700 is realized as program code stored within computer readablememory units of an intelligent controller and a target device of network5. At step 710, the intelligent controller device, e.g., STB 13 and TV11 (used as the display unit), locates electronic devices coupled tosystem 5. This process utilizes well known IEEE 1394 communicationprotocol mechanisms. At step 712, the intelligent controller reads thecomputer readable memory units of a target device coupled to the network5 and discovers that this target device has a panel subunit datastructure 314 defined therein. At step 714, the intelligent controllerdevice downloads the descriptor information and the current statusdescriptor table for the target device and displays a user interface onthe display screen of the intelligent controller based on the downloadedinformation. If the intelligent controller device has limited memoryresources, then the panel subunit information can be downloaded andprocessed in portions.

At step 714, the control objects of the panel subunit describe the look,shape, grouping and location for each user input element and eachinformation display element for the user interface. Should theintelligent controller be limited in display capability, then textstrings are displayed for the groups and/or for the control objects andthese text strings can be displayed in a hierarchical format (e.g.,using a tabbed-panel display).

At step 716 of FIG. 9, the intelligent controller allows the user tointeract with the user interface including accepting predefined orgeneric user events from the user. Each control object contains anobject type and each object type defines a user action that can takeplace with respect to the control object. For instance, buttons are“PUSHED” or “PUSHED AND HELD” or “RELEASED” and sliders and rotators canbe moved to “SET A VALUE.” Toggle switches can be moved between twopositions, e.g., “MOVED RIGHT” or “MOVED LEFT” or “MOVED UP” or “MOVEDDOWN.” Other user events include setting a text value, e.g., SET TEXTVALUE, or setting a numeric value, SET VALUE, etc. These user events aredefined by the control objects themselves and the intelligent controllerdoes not interpret the meanings of these events for any target device.

At step 716, irrespective of the type of user input device, e.g.,keyboard, mouse and mouse button, remote control unit, pen and stylus,light pointer, joystick, etc., the intelligent controller translates theinteraction between these user input devices and the user into a genericuser event core recognized by the panel subunit 314 of the presentinvention. For instance, a button control object can be “PRESSED” andthen “RELEASED” by selecting it with a mouse or selecting it with akeyboard or with a remote control button push. In either case, the userevent is “PRESSED” or “RELEASED” with respect to the control object.

At step 718 of FIG. 9, any user events detected by the intelligentcontroller are forwarded over the network 5 to the target device. Thetarget device then interprets the user event and takes the appropriateaction based on its programming. The programming used by the targetdevice at step 718 is the same programming that is already present inthe target device for responding to the input devices physically locatedon the target device. In this case, any target device having physicalcontrols located thereon already is programmed with the required actionsto take upon these controls being directly pushed by a user. The presentinvention takes advantage of this pre-existing functionality within eachtarget device. A received user event may trigger a change in one or moreof the states of the control objects defined within the panel subunit ofthe present invention. Upon a change in state, the status descriptor 500of the panel subunit changes thereby notifying the intelligentcontroller of a state change.

At step 720, the intelligent controller downloads the status descriptorto determine which control object changed states. Next, the intelligentcontroller updates the displayed user interface to reflect the change.For instance, if the button state changed from released to pressed, thenthe intelligent controller may display a new image for the button statebeing pushed. Alternatively, if the state of the VCR tape mechanismchanges from standby to play, an image within LCD panel 214 might becomeanimated showing the tape playing, etc. At step 722, the generic userevents cause the target device to implement a certain action, e.g.,play, pause, etc. It is appreciated that step 722 can occur before step720. At step 724, processing returns to step 716 to check for a nextuser action.

In operation, the intelligent controller is not burdened with keepingstate tables or by interpreting the meaning of the user events. Theseinterpretations are performed by the target device thereby providing thepanel subunit with a large amount of flexibility for adapting to newstandards and control types. Furthermore, by providing a range ofpossible display representations, the present invention provides aflexible user interface for intelligent controllers having robustdisplay capabilities and also for those controllers havingunsophisticated displays. The panel subunit of the present inventiondefines generic user input events, core data structures which define alimited set of user actions or events and display elements and a basiccommunication protocol is used.

FIGS. 10-12 illustrate another example of the present invention. FIG. 10illustrates a simulated or “virtual” keyboard 540 that can be generatedfor a target device using the panel subunit of the present invention.The virtual keyboard 540 can be used to control a “black box” devicethat itself has no physical keys or LEDs and whose control panel ispurely virtual. In this case, the black box has no physical equivalentkeyboard and relies on the intelligent controller for access to itsfunctionality. In one example, the target device can be a subpanel foran intelligent television which has embedded software that requires userinput, e.g., for web surfing or similar tasks.

The virtual keyboard 540 includes groups of controls where each controldefines a key or an LED. Each element is represented by its own controlobject. The virtual keyboard 540 of FIG. 10 includes several groups(e.g., main keys, function keys, keypad keys, etc.) with variousdimensions and layouts. A first group 542 includes only the ESC keywhile the function keys, F1-F(n), are grouped into group 544. Thestandard alpha keys, the tab, caps lock, shift, control, etc., keys aregrouped into group 546. The numeric keys and operator keys are groupedinto group 548. Also included are a numlock LED 554, a caps lock LED 556and a scroll lock LED 558. A power on key 560 is shown along with aspecial button 550 having an LED 552 therein. An LED 552 embedded in thekey 550 can be modeled as an LED which can be turned on or off with theappropriate panel subunit command. Thus, a key with an LED is modeled asa hybrid control object. Group 565 includes LEDs 554, 556, 558, 552 andbuttons 560 and 550.

FIG. 11 illustrates the control object descriptor information within thepanel subunit needed to realize the hybrid button 550 as an example inaccordance with the present invention. Fields 572-578 define a controlobject. Field 572 indicates that the control object is a “HYBRID” type.Field 574 indicates that two control object definitions are included inthis hybrid. Field 576 is a pointer to control object 610 (control0)while field 578 points to control object 640 (control1).

With respect to control0 control object 610, field 612 indicates thatthe object is a “button” type and field 614 indicates the button image614 a. Field 616 indicates the button dimensions (x, y) and field 618indicates a group identifier for group 565. Field 620 indicates therelative position of button 550 within the boundary of group 565. Field622 indicates the range of values for the button 550 (e.g., 0 and 1).Field 624 represents the optional AV/C command, if any, corresponding tothe states of button 550. Field 626 is the optional target deviceidentification. Field 628 is the string “Special” for displays that mayhave only text display capability. The help string, if any, is in field630.

With respect to control1 control object 640, field 642 of FIG. 11indicates that the object is an “LED” type and field 644 indicates theimages for the different states of the LED, e.g., green for the ON stateand black for the OFF state. Field 646 indicates the LED imagedimensions (x, y) and field 648 indicates a group identifier for group565. Field 650 indicates the relative position of LED 552 within theboundary of group 565. Field 652 indicates the range of values for thebutton 550 (e.g., ON and OFF). Field 544 represents the optional AV/Ccommand, if any, corresponding to the states of LED 552. Field 656 isthe optional target device identification. Field 658 is the string forLED 552 for displays that may have only text display capability. Thehelp string, if any, is in field 660 Using the examples of FIG. 11, thecontrol objects for the remainder of FIG. 10 can be realized.

FIG. 12 illustrates steps performed by the intelligent controller andthe target device, and communications there between, for interactingwith the virtual keyboard 540 of FIG. 10. At step 805, the intelligentcontroller sends a request 807 to the target device for a notificationupon any changes of the status descriptor for the virtual keyboard 540.At step 830, the target device accepts the request 807 and generates aninterim signal 832 to the intelligent controller acknowledging therequest 807. At step 810, the user interfaces with the virtual keyboard540 such that the user event “PRESS” is indicated on the caps lock keyof group 546. The user event “PRESS” caps lock is then transmitted 812from the intelligent controller to step 835 of the target device.

At step 835, the target device takes any action required by this userevent according to its own preset programming. The status descriptorchanges and this causes a status response (e.g., to the PRESS command)to be generated by the target device. At step 835, the target deviceforwards a new status 837 of the caps lock key to the intelligentcontroller indicating that the caps lock key is now pressed. Only afterreceiving the new status information 837 does the intelligent controllerchange the image of the caps lock button on the display to indicate thatit is now pressed. As a side effect of the action taken by the targetdevice, at step 840, the state of the caps lock LED 556 changes from OFFto ON. The status descriptor changes and this causes a status updatemessage to be generated by the target device. This change in status isreported by message 822 to the intelligent controller in response to achange in the status descriptor. The intelligent controller, in responseto message 822, reads the status descriptor 845 of the target device todetermine which control object changed status. At 827, it is determinedand returned that the status of the LED 556 changed from OFF to ON. Onlyin response to receiving the new status information does the intelligentcontroller, at step 825, then update the image for the LED 556 fromblack to green to indicate the new status of ON.

It is appreciated that a direct interaction with the physical controlsof the target device at step 840 can also cause a state change in thestatus descriptor which would then cause a notification of a statuschange to be forwarded to the intelligent controller. This action wouldalso cause a change in the user interface displayed on the intelligentcontroller as described above The process can be repeated.

One embodiment of the present invention describes the representation ofdevice capabilities which have some types of physical control ordisplay, e.g., something that is user-visible and that would bemanipulated by a human. However, the panel subunit of the presentinvention can be extended to describe how to access functionality thatis “built-in” to a device but which does not have a physical externalbutton to access it. For example, many digital set-top-boxes can containone or more MPEG2 decoders, which contain very useful media processingfunctions. However, it is very unlikely that there would be an MPEG2button on the device for the user to push. Rather, the panel subunit ofthe present invention can be used to define interface objects within adescriptor that represent “virtual” buttons and dials for interfacingwith the MPEG2 decoder. Therefore, the capabilities of the MPEG2 decoderand the means to access its capabilities can be described using thepresent invention even though no physical interface elements exist onthe set-top-box.

In furtherance of the above, because the panel subunit 314 of thepresent invention defines various types of controls and theirattributes, it is possible for a “black box” device to be built whichhas no physical controls, but relies on its panel subunit of the presentinvention as its only means of being controlled (e.g., the virtualkeyboard 540). Such a target device might be designed for situationswhere the hardware can be located in a remote or hidden location and theuser control center (e.g., the intelligent controller) is at a differentlocation. In this case, the target device would not have physicalcontrols on its surface because they would never be used directly by aperson.

Another embodiment of the present invention is drawn to the types ofinformation or attributes that are provided by the functionalitydescriptors of the panel subunit. For example, the present inventiondescribes various attributes for a button control including its physicalappearance, size and shape, a text string describing the function,e.g.,.“play,” possibly a help string describing how to use it, and somestandard commands for manipulating that control, e.g., PUSH BUTTON orSET BUTTON VALUE TO 1. A variation of this functionality can add someother attributes that may be useful either in a general way or avender-specific way.

Table GUI Extension to Panel Subunit

Although the panel subunit mechanism allows a target to communicate userinterface information to a controller, the controller may reorder theelements displayed on its screen to accommodate other limitations, e.g.,screen size, etc. If a controller does not have the ability to display arich interface, it may alter the order and appearance of the interfaceelements (“objects”) in order to accommodate its display capability. Assuch, a target using only the panel subunit as described above has noguarantee that its interface elements will be displayed in anyprescribed order or appearance as specified by the target. Furthermore,controllers are typically limited in terms of screen size and memorycapabilities and may be therefore incapable of displaying a large amountof information (e.g., an entire electronic programming guide) all atonce. To that end, the table GUI element extension to panel subunit ofpresent embodiment provides a way for a target to define a table GUI tobe displayed on the controller. Further, the table GUI element extensionof the present embodiment provides a way for a controller to displaytabulated information one section at a time. The table GUI elementextension of the present invention also enables users to performscrolling. This is particularly useful in cases such as electronicprogram guides (EPGs) where vertically aligned and horizontally alignedinformation carries meaning within the guide and where the controllercan display a small section of EPG information at a time.

FIG. 13 illustrates an exemplary network 850 of electronic devices thatmay make use of the table GUI element extension of the presentinvention. This exemplary network 850 (connected via a high speed bus,e.g., the IEEE 1394 bus) contains a controller 852 (e.g., digitaltelevision unit) coupled to set-top-box device 856 (the “target”). TheSTB 856 receives content via a cable input 858. STB 856 may also receivethrough cable input 858 electronic programming guide information. Otherdevices within the exemplary network 850 include an audio/video serverdisk 854, a VCR 860, a CD 862 and a digital camera 864. To implement thepresent invention, only the target 856 and the controller 852 arerequired. The controller 852, in this case, includes a remote controlunit 866 which contains special function keys, such as, a guide button866 a, a selection up button 866 a, a selection down button 866 c, aselection right button 866 b and a selection left button 866 e. Buttons866 a-866 c and 866 e are used for altering the focus of a displayedimage during user navigation. Focus refers to a highlighted or otherwisedistinguished screen object. When pressed, the guide button 866 d causesan EPG 868 to appear on the controller screen 852.

FIG. 14 illustrates an exemplary EPG 868 in more detail. EPG 868includes an EPG table 874 containing vertically and horizontally alignedinformation representing programs. A particular selected program 876 isalso shown highlighted. Each separate display item can be considered anobject, and each object is displayed with the particular order shown inFIG. 14, otherwise the EPG 868 will not make any sense to a user. Alsoshown in FIG. 14, but optional, is a decimated video image 870 of theselected program 876 and a text description 872 of the selected program876.

The present embodiment of the invention, a table GUI element extensionof panel subunit, enables the EPG table 874 to be displayed by thecontroller 852. FIG. 15 illustrates a particular implementation of atable GUI element descriptor 1500. In the present embodiment, table GUIelement descriptor 1500 is maintained by computer readable memory unitsof a target (e.g., STB 856). Further, in the present embodiment, thetable GUI element descriptor 1500 presents its information to thecontroller such that a table user interface can be generated by thecontroller.

As illustrated in FIG. 15, “descriptor_length” field 1502 contains thelength of the table GUI element descriptor 1500. “List_type” field 1504contains list type information for indicating to a controller thatdescriptor 1500 describes a table GUI element. “Attributes” field 1506describes the attributes of the table GUI element. “Size_of_listspecific information” field 1508 describe the size of the list specificinformation. “Content_width” field 1510 and “content_height” field 1512describe the dimensions (width and height) of the table to be displayed,and in one embodiment is being represented in screen coordinates.“Number_of_x_item” field 1514 describes a number of columns of the tableGUI element. “Number_of_y_item” field 1514 describes a number columns ofthe table GUI element.

It should be appreciated that, in the present EPG example, due toscreen-size limitations, the controller can only display a small sectionof available EPG information at a time. This is accomplished by usingfields 1518, 1520, 1522 and 1524 of the descriptor 1500.“Start_item_of_display(x)” field 1518 and “start_item_of_display(y)”field 1520 describe, respectively, the starting column number and thestarting row number of a table to be displayed. “Display_range(x)” field1522 and “display_range(y)” field 1524 describe, respectively, thenumber of columns and the number of rows to be displayed. Because only asmall section of available EPG information is displayed at a time, thetarget does not need to transmit the all the EPG information to thecontroller. Rather, the target may transmit to the controller onlyinformation pertaining to the section to be displayed. The controllerwould then generate a table based on such information.

Table GUI element descriptor 1500 also includes a “selectable” field1526 for describing whether each respective objects of the table GUIelement is selectable. “Optional_attributes_list” field 1528 describesan optional attributes list for the table GUI element.“Number_of_links(n)” field 1530 describes a number of links for each ofthe objects of the table GUI element. “Released_label_link” field 1532describes a released label link that points to a memory area storing thelabel for an object when it is released. “Released_bitmap_link” field1534 describes a released bitmap link that points to a memory areastoring the bitmap for the object when it is released.“Pressed_label_link” field 1536 describes a pressed label link thatpoints to a memory area storing the label for the object when it ispressed. “Pressed_bitmap_link” field 1538 describes a pressed bitmaplink that points to a memory area storing the bitmap for the object whenit is pressed. “Focused_label_link” field 1540 describes a focused labellink that points to a memory area storing the label for the object whenit is focused during focus navigation. “Focused_bitmap_link” field 1542describes a focused bitmap link that points to a memory area storing thebitmap for the object when it is focused. “Optional_link_list” field1544 describes other optional link list for the object. In the presentembodiment, each object of the table GUI element has its respectivelinks.

FIGS. 16A-16D illustrate exemplary data flow between a controller 852and a target 856 for generating table GUI in accordance with oneembodiment of the present invention. In this embodiment, the target isresponsible for generating and maintaining a table GUI elementdescriptor. The controller retrieves the descriptor from the target, andgenerates a table GUI according to the definitions provided by the tableGUI element descriptor. Because the table GUI element descriptor definesthe rows and columns of a table to be displayed, elements of the tableGUI are- displayed in the exact order as specified by the target.

FIG. 16A illustrates, by data flow 1610 a, the controller 852 sending totarget 856 a request to display an EPG. In one embodiment of the presentinvention, the request is generated by the controller 852 when a userpresses a button on a remote (e.g., button 866 d of remote control 866).Further, in the present embodiment, the request be sent using panelsubunit mechanisms discussed above.

FIG. 16B illustrates, by data flow 1610 b, the controller 852 retrievinga table GUI element descriptor from target 856. In the presentembodiment, the table GUI element descriptor defines an EPG table 1620to be displayed. The EPG table 1620, as illustrated includes two columnsand five rows and corresponds to a section 1655 of available EPGinformation 1650. Data flow 1610 b may also include definitions of otherdisplay elements such as display labels, scroll bars, etc.

FIG. 17A illustrates a more detailed view of the EPG table 1620. Asillustrated in FIG. 17A, EPG table 1620 includes five rows 1621, 1623,1625, 1627 and 1629. EPG table 1620 also has two columns 1622-1624. The“objects” or “cells” of the EPG table 1620, as well as their positionswithin the matrix, are defined by the table GUI element descriptor(e.g., descriptor 1500). Also illustrated in FIG. 17A is a focusedobject 1626.

As shown by FIG. 16C, in response to a user input, the controller 852sends a focus navigation command (via data flow 1610 c) to the target856.

In FIG. 16D, the target 856 updates the table GUI element descriptor. Asshown by data flow 1610 d, the controller 852 retrieves the updatedtable GUI element descriptor and constructs a new EPG table 1630.

A more detailed view of the new EPG table 1630 is illustrated in FIG.17B. The dimension of the new EPG table 1630 is the same as that of EPGtable 1620. However, the new EPG table 1630 includes a new row 1631. Row1629 of EPG table 1620 is no longer displayed. Essentially, the new EPGtable 1630 displays another section 1656 of all available EPGinformation 1650. According to the present embodiment, the new EPG table1630 is brought about by modifying the starting row number value (e.g.,field 1520) of the table GUI element descriptor. Also illustrated is anew focused object 1628 brought about by the focus navigation command.

FIG. 18 illustrates a flow diagram 1800 of steps performed within anelectronic network (e.g., network 850) for constructing an EPG tableusing a table GUI element extension to panel subunit according to oneembodiment of the present invention. At step 1810, target (e.g., a setof box) receives a complete electronic programming guide (EPG) via adigital service connection, and generates a table GUI elementdescriptor. In the present embodiment, the GUI element descriptor (e.g.,descriptor 1500) defines an EPG table to be displayed. Moreparticularly, the table GUI element descriptor defines the starting rownumber and column number, the display range, and labels and bitmaps forobjects of the EPG table. Further, objects of the EPG table areaccording to channel numbers and show times.

At step 1820, the target receives a user command from the controllerrequesting an EPG table to be displayed on the controller. In oneembodiment, the user command may be sent using panel subunit mechanismsdiscussed above. In another embodiment, the user command may be sentusing a command pass-through mechanism. The command pass-throughmechanism is discussed in more details in co-pending U.S. patentapplication Ser. No. 09/585,706, (TBD), entitled “COMMAND PASS-THROUGHFUNCTIONALITY IN PANEL SUBUNIT,” by Hisato Shima, Atsushi Suzuki andTakuya Nishimura, which is hereby incorporated by reference.

At step 1830, in response to a user selection, the controller reads thetable GUI element descriptor that is defined by the target, andconstructs an EPG table based on information defined by the descriptor.For instance, if the table GUI element descriptor specifies that thestarting row number is P and the starting column number is Q and thedisplay ranges are X rows and Y columns, then the controller willdisplay an EPG table having X rows and Y columns starting from rownumber P and column number Q.

At step 1840, the user interfaces with the EPG table by providing afocus navigation change. In one implementation, this occurs by thepressing of a defined focus navigation button (e.g., arrow up, arrowdown, arrow right or arrow left). The navigation tool can be located onthe DTV unit, or on a remote control device, or it could be virtual(e.g., on screen displayed).

At step 1850, the user selection is communicated to the target. In oneimplementation, step 1850 is realized using the command pass-throughmechanism. In an alternate embodiment, the panel subunit communicationarchitecture as described with respect to FIGS. 1-12, is used.Specifically, a user event within the panel subunit can be used torealize step 1850.

At step 1860 of FIG. 18, in response to focus navigation selection, thetarget updates the table GUI element descriptor. Particularly, if thefocus navigation change calls for the EPG table to display anothersection of the complete EPG, then the target may have to modify thestarting row number field and the starting column number field of thedescriptor. It should be noted that, however, it may not be necessaryfor the target to modify the descriptor because the focus navigationchange may not call for another section of the complete EPG to bedisplayed.

At step 1870, the controller reads the updated table GUI elementdescriptor, and displays an updated EPG table. In the presentembodiment, steps 1840 to 1870 may be repeated for additional focusnavigation changes.

It is appreciated that by using the table GUI element descriptor todefine a table-like interface, the present invention provides anefficient way for a target to communicate a screen of information fordisplay on a controller. It is particularly advantageous for the displayof information that needs to be displayed in a particular arrangement(e.g., EPG information) and also when used in conjunction withcontrollers that do not have robust processing capabilities and thosethat may not have sufficient memory to store the complete EPG.

Focused Bitmap

The present invention provides a button GUI element descriptor thatdefines the appearance of a button element when displayed by acontroller. Significantly, the button GUI element descriptor defines fora button element one bitmap to be displayed when out of focus andanother bitmap to be displayed when the button element is in focus. Inthis way, the target would be able to control the focused design of thebutton.

FIG. 19 illustrates a particular implementation of a button GUI elementdescriptor 1900. In the present embodiment, button GUI elementdescriptor 1900 is maintained by computer readable memory units of atarget (e.g., STB 856). As illustrated in FIG. 19, “descriptor_length”field 1902 contains the length of the button GUI element descriptor1900. “List_type” field 1904 contains list type information forindicating to a controller that descriptor 1900 describes a button GUIelement. “Attributes” field 1906 describes the attributes of the buttonGUI element. “Size_of_list_specific information” field 1908 describesthe size of the list specific information.

“Button_width” field 1910 and “button_height” field 1912 describe thedimensions (width and height) of the button to be displayed, and in oneembodiment is being represented in screen coordinates. Button GUIelement descriptor 1900 also includes an “optional_attributes_list”field 1914 describes an optional attributes list for the button GUIelement. “Number_of_links(n)” field 1916 describes a number of links foreach of the objects of the button GUI element.

Button GUI element descriptor 1900 of the present invention includes a“normal_label_link” field 1918 describes a released label link thatpoints to a memory area storing the label for an object when it is notin focus during focus navigation. “Normal_bitmap_link” field 1920describes a released bitmap link that points to a memory area storingthe bitmap for the object when it is not in focus. Significantly, buttonGUI element descriptor 1900 of the present invention includes a“focused_label_link” field 1922 and a “focused_bitmap_link” field 1924.“Focused_label_link” field 1922 describes a focused label link thatpoints to a memory area storing the label for the object when it isfocused during focus navigation. “Focused_bitmap_link” field 1924describes a focused bitmap link that points to a memory area storing thebitmap for the object when it is focused. “Optional_link_list” field1926 describes other optional link list for the object. In the presentembodiment, each object of the button GUI element has its respectivelinks.

FIGS. 20A and 20B illustrate an exemplary panel subunit GUI 2000 asdisplayed by a controller (e.g., controller 852) using button GUIelement descriptors of the present embodiment. As illustrated in FIG.20A, button 2010 of the panel subunit 2000 is in focus and is displayedby the controller with a focused bitmap design. In the presentembodiment, the focused bitmap design is defined by“focused_bitmap_link” field 1924 of button GUI element descriptor 1900.In FIG. 20A, buttons 2020 and 2030 of the panel subunit 2000, however,are not in focus and are displayed with a normal bitmap design. Thenormal bitmap design is defined by “normal_bitmap_link” field 1920 ofthe descriptor 1900.

In FIG. 20B, button 2010 is no longer in focus and button 2020 is infocus. Therefore, a normal bitmap is displayed for the button 2010 and afocused bitmap is displayed for button 2020. Because the button GUIelement descriptor 1900 includes a normal bitmap link and a focusedbitmap link, the target would be able to have more control over how abutton element would appear on the controller. Additionally, a richgraphical user interface would be achievable even on a controller withlimited capabilities.

Default Focus

One embodiment of the present invention provides a panel GUI elementdescriptor that includes a focused identifier attribute indicating apre-determined element of the panel subunit GUI as default focus. Inthis way, the target would be able to control the default focus of thepanel subunit GUI when displayed by a controller. In addition, incertain cases, the controller may display meaningful information onlywhen a default focus has been pre-determined.

FIG. 21 illustrates a particular implementation of a panel GUI elementdescriptor 2100. In the present embodiment, panel GUI element descriptor2100 is maintained by computer readable memory units of a target (e.g.,STB 856). As illustrated in FIG. 21, “descriptor_length” field 2102contains the length of the panel GUI element descriptor 2100.“List_type” field 2104 contains list type information for indicating toa controller that descriptor 2100 describes a panel GUI element.“Attributes” field 2106 describes the attributes of the panel GUIelement. “Size_of_list_specific_information” field 2108 describes thesize of the list specific information.

“Aspect_ratio” field 2110 describes the aspect ratio (e.g., ratiobetween height and width) of the panel GUI to be displayed. Panel GUIelement descriptor 2100 also includes an “optional_attributes_list”field 2114 describes an optional attributes list for the panel GUIelement. “Number_of_links(n)” field 2116 describes a number of links foreach of the objects of the panel GUI element. Panel GUI elementdescriptor 2100 may include other fields for storing other attributes ofthe panel GUI element.

Significantly, panel GUI element descriptor 2100 of the presentinvention includes a “focused_id” field 2112 for storing an identifieridentifying a particular element (e.g., button) as a default focus. Inaccordance with the present embodiment, panel GUI element descriptor2100 defines a panel GUI to be displayed, and causes the controllerdisplaying the panel GUI to display the designated button as the defaultfocus.

FIGS. 22A and 22B illustrate data flow between controller 852 and target856 of network 850 using the panel GUI element descriptor in accordancewith the present embodiment. As shown by FIG. 22A, in response to a userselecting the “GUIDE” button 866 d (FIG. 13) on a remote control device866, for instance, a command pass-through code 876 c is forwarded to thetarget 856 (e.g., using the 1394 asynchronous connection) whichrecognizes this command as a request for the display of EPG information.It is appreciated that any of a number of different mechanisms can beused to signal a request for EPG information and the commandpass-through mechanism shown in FIG. 22A is just one example.

As shown in FIG. 22B, the target 856 then forwards the controller an EPGpanel GUI element which is displayed on a screen of the controller 852.The EPG panel GUI element 868 has a default focus selection according tothe “focused_id” attribute of the panel GUI element descriptor 2100. Thedefault focus selection (“default focus”) is 876, “National Geographic.”After the EPG panel GUI is displayed, a user may then select otherelements of the EPG via a focus navigation change, e.g., selection ofthe up button 866 a (FIG. 13).

Also show in FIG. 22B is decimated video 870 that corresponds to thechannel to which the target 856 is tuned before EPG 868 is displayed.The decimated video 870 also corresponds to the default focus selection876. Without using the default focus identifier attribute of the presentembodiment, the focus of the EPG table may be arbitrarily determined bythe controller and may bear no correlation to the video signals thattarget 856 is sending the controller. This disadvantage is overcome byusing the default focus selection mechanism of the present embodiment.By defining the default focus, the target would be able to determinewhich object of the panel GUI is in focus when the panel GUI isinitially generated. In this way, the controller would be able todisplay meaningful information and provide a rich graphical userinterface.

Font Style Attributes for Text Element

Another embodiment of the present invention provides a text GUI elementdescriptor that includes a font style attribute dictating whether thetext GUI element should be displayed as bold, underlined and/orreversed. In this way, the target device would be able to exercise morecontrol over the “look-and-feel” of the GUI as displayed by thecontroller device such that more sophisticated GUIs can be realized.

FIG. 23 illustrates a particular implementation of a text GUI elementdescriptor 2300. In the present embodiment, text GUI element descriptor2300 is maintained by computer readable memory units of a target (e.g.,STB 856). As illustrated in FIG. 23, “descriptor_length” field 2302contains the length of the text GUI element descriptor 2300. “List_type”field 2304 contains list type information for indicating to a controllerthat descriptor 2300 describes a text GUI element. “Attributes” field2306 describes the attributes of the text GUI element.“Size_of_list_specific_information” field 2308 describes the size of thelist specific information.

“Text_height” field 2310 and “text_width” field 2312 describe thedimensions of the text element to be displayed and may be expressed inscreen coordinates. Text GUI element descriptor 2300 also includes an“optional_attributes_list” field 2322 that describes an optionalattributes list for the text GUI element. “Number_of_links(n)” field2324 describes a number of links for the text GUI element. Text GUIelement descriptor 2300 may include other fields for storing otherattributes of the text GUI element.

Significantly, text GUI element descriptor 2300 of the presentembodiment includes a “bold” field 2316, an “underline” field 2318 and a“reverse” field 2320 for storing attributes that define the style of thetext GUI element to be displayed.

FIG. 24 illustrates an exemplary EPG 2400 defined by descriptors thatinclude text GUI element descriptor 2300 and displayed by controller 852in accordance with an embodiment of the present invention. As shown inFIG. 24, EPG 2400 includes bolded characters 2410, underlined characters2420, underlined and bolded characters 2430 and reversed characters2440. Bolded characters 2410 are brought about by using the “bold” field2316 of the text GUI element descriptor. Underlined characters 2420 arebrought about using the “underlined” field 2318 of the text GUI elementdescriptor. Bolded and underlined characters 2430 are brought aboutusing the “bold” field 2316 and “underlined” field 2318. Reversedcharacters 2449 (e.g., characters that are displayed with the foregroundand background colors reversed) are brought about by using the “reverse”field 2320. It should be appreciated that, in accordance with thepresent embodiment, many different combinations of bold, underline andreverse can also be used.

The preferred embodiments of the present invention, extended elementsand mechanisms for providing a rich user interface in panel subunit,have thus been described. While the present invention has been describedin particular embodiments, it should be appreciated that the presentinvention should not be construed as limited by such embodiments, butrather construed according to the below claims.

What is claimed is:
 1. In a system having a controller device and atarget device, a method for realizing complex graphical user interface(GUI) on said controller device, said method comprising steps of: saidcontroller device receiving a button GUI element descriptor from saidtarget device, wherein said button GUI element descriptor defines abutton element to be displayed and wherein said button GUI elementdescriptor further defines a first bitmap image to be displayed whensaid button element is out of focus and a second bitmap image to bedisplayed when said button element is in focus; and said controllerdevice displaying said button element as part of an on-screen display,wherein said button element comprises said first bitmap image when saidbutton element is out of focus and wherein said button element comprisessaid second bitmap image when said button element is in focus.
 2. Amethod as recited in claim 1 wherein said button GUI element descriptordefines a first button label to be displayed when said button element isout of focus.
 3. A method as recited in claim 2 wherein said button GUIelement descriptor further defines a second button label to be displayedwhen said button element is in focus.
 4. A method as recited in claim 1wherein said on-screen display comprises an electronic program guide(EPG).
 5. A method as recited in claim 1 wherein said controller devicecomprises a digital television.
 6. A method as recited in claim 1wherein said target device comprises a set-top box.
 7. A controllerdevice configured for coupling to a target device via a digital bus,said controller device comprising: means for receiving a button GUIelement descriptor from said target device, wherein said button GUIelement descriptor defines a button element to be displayed and whereinsaid button GUI element descriptor further defines a first bitmap imageto be displayed when said button element is out of focus and a secondbitmap image to be displayed when said button element is in focus; andmeans for displaying said button element as part of an on-screendisplay, wherein said button element comprises said first bitmap imagewhen said button element is out of focus and wherein said button elementcomprises said second bitmap image when said button element is in focus.8. A controller device as recited in claim 7 wherein said button GUIelement descriptor defines a first button label to be displayed whensaid button element is out of focus.
 9. A controller device as recitedin claim 8 wherein said button GUI element descriptor further defines asecond button label to be displayed when said button element is infocus.
 10. A controller device as recited in claim 7 wherein saidon-screen display comprises an electronic program guide (EPG).
 11. Acontroller device as recited in claim 7 wherein said target devicecomprises a set-top box.
 12. A target device configured for coupling toa controller device via a digital bus, said target device comprising:means for storing a button GUI element descriptor, wherein said buttonGUI element descriptor defines a button element to be displayed andwherein said button GUI element descriptor further defines a firstbitmap image to be displayed when said button element is out of focusand a second bitmap image to be displayed when said button element is infocus; and means for sending said button GUI element descriptor to saidcontroller device such that said controller device displays said firstbitmap image when said button element is out of focus and wherein saidcontroller device displays said second bitmap image when said buttonelement is in focus upon receiving said button GUI element descriptor.13. A target device as recited in claim 12 wherein said descriptorinformation defines a first button label to be displayed when saidbutton element is out of focus.
 14. A target device as recited in claim13 wherein said descriptor information further defines a second buttonlabel to be displayed when said button element is in focus.
 15. A targetdevice as recited in claim 12 wherein said on-screen display comprisesan electronic program guide (EPG).
 16. A target device as recited inclaim 12 wherein said controller device comprises a digital television.17. In a system having a controller device and a target device, a methodfor realizing complex graphical user interface (GUI) on said controllerdevice, said method comprising steps of: said controller devicereceiving a table GUI element descriptor from said target device,wherein said table GUI element descriptor defines a matrix that includesvertically and horizontally aligned information, and wherein said tableGUI element descriptor further defines an on-screen display fordisplaying a portion of said matrix; and said controller devicedisplaying said on-screen display according to said table GUI elementdescriptor.
 18. A method as recited in claim 17 wherein said table GUIelement comprises: a first attribute corresponding to a total number ofcolumns of said matrix; and a second attribute corresponding to a totalnumber of rows of said matrix.
 19. A method as recited in claim 18wherein said table GUI element comprises: a third attributecorresponding to a number of columns of said matrix to be displayed bysaid on-screen display; and a fourth attribute corresponding to a numberof rows of said matrix to be displayed by said on-screen display.
 20. Amethod as recited in claim 19 wherein said table GUI element comprises:a fifth attribute corresponding to a column number of a first column ofsaid on-screen display; and a sixth attribute corresponding to a rownumber of a first row of on-screen display.
 21. A method as recited inclaim 17 wherein said table-like GUI comprises an electronic programguide (EPG).
 22. A method as recited in claim 17 wherein said controllerdevice comprises a digital television.
 23. A method as recited in claim17 wherein said target device comprises a set-top box.
 24. A controllerdevice configured for coupling to a target device via a digital bus,said controller device comprising: means for receiving a table GUIelement descriptor from said target device, wherein said table GUIelement descriptor defines a matrix that includes vertically andhorizontally aligned information, and wherein said table GUI elementdescriptor further defines an on-screen display for displaying a portionof said matrix; and means for displaying said on-screen displayaccording to said table GUI element descriptor.
 25. A controller deviceas recited in claim 24 wherein said table GUI element descriptorcomprises: a first attribute corresponding to a total number of columnsof said matrix; and a second attribute corresponding to a total numberof rows of said matrix.
 26. A controller device as recited in claim 25wherein said table GUI element descriptor comprises: a third attributecorresponding to a number of columns of said matrix to be displayed bysaid on-screen display; and a fourth attribute corresponding to a numberof rows of said matrix to be displayed by said on-screen display.
 27. Acontroller device as recited in claim 26 wherein said table GUI elementdescriptor comprises: a fifth attribute corresponding to a column numberof a first column of said on-screen display; and a sixth attributecorresponding to a row number of a first row of on-screen display.
 28. Acontroller device as recited in claim 24 wherein said on-screen displaycomprises an electronic program guide (EPG).
 29. A controller device asrecited in claim 24 wherein said target device comprises a set-top box.30. A target device configured for coupling to a target device via adigital bus, said controller device comprising: means for storing atable GUI element descriptor, wherein said table GUI element descriptordefines a matrix that includes vertically and horizontally alignedinformation, and wherein said table GUI element descriptor furtherdefines an on-screen display for displaying a portion of said matrix;and means for sending said table GUI element descriptor to saidcontroller device such that said controller device displays saidon-screen display according to said table GUI element descriptor.
 31. Atarget device as recited in claim 30 wherein said table GUI elementdescriptor comprises: a first attribute corresponding to a total numberof columns of said matrix; and a second attribute corresponding to atotal number of rows of said matrix.
 32. A target device as recited inclaim 31 wherein said table GUI element descriptor comprises: a thirdattribute corresponding to a number of columns of said matrix to bedisplayed by said on-screen display; and a fourth attributecorresponding to a number of rows of said matrix to be displayed by saidon-screen display.
 33. A target device as recited in claim 32 whereinsaid table GUI element descriptor comprises: a fifth attributecorresponding to a column number of a first column of said on-screendisplay; and a sixth attribute corresponding to a row number of a firstrow of on-screen display.
 34. A target device as recited in claim 30wherein said on-screen display comprises an electronic program guide(EPG).
 35. A target device as recited in claim 30 wherein saidcontroller device comprises a digital television.
 36. In a system havinga controller device and a target device, a method for realizing complexgraphical user interface (GUI) on said controller device, said methodcomprising steps of: said controller device receiving a panel GUIelement descriptor from said target device, wherein said panel GUIelement descriptor defines an on-screen display that includes aplurality of elements, and wherein said panel GUI element descriptorfurther includes a focused identifier attribute that indicates apre-determined one of said plurality of elements as default focus; saidcontroller device displaying said on-screen display according to saidpanel GUI element descriptor; and said controller device choosing saidpre-determined element as focus.
 37. A method as recited in claim 36wherein said on-screen display comprises an electronic programming guide(EPG).
 38. A method as recited in claim 36 wherein said on-screendisplay comprises a pop-up menu.
 39. A method as recited in claim 36wherein said controller device comprises a digital television.
 40. Amethod as recited in claim 36 wherein said target device comprises aset-top box.
 41. A controller device configured for coupling to a targetdevice via a digital bus, said controller device comprising: means forreceiving a panel GUI element descriptor from said target device,wherein said panel GUI element descriptor defines an on-screen displaythat includes a plurality of elements, and wherein said panel GUIelement descriptor further includes a focused identifier attribute thatindicates a pre-determined one of said plurality of elements as defaultfocus; means for displaying said on-screen display according to saidpanel GUI element descriptor; and means for choosing said pre-determinedelement as focus.
 42. A controller device as recited in claim 41 whereinsaid on-screen display comprises an electronic programming guide (EPG).43. A controller device as recited in claim 41 wherein said on-screendisplay comprises a pop-up menu.
 44. A controller device as recited inclaim 41 wherein said controller device comprises a digital television.45. A controller device as recited in claim 41 wherein said targetdevice comprises a set-top box.
 46. A target device configured forcoupling to a controller device via a digital bus, said target devicecomprising: means for storing a panel GUI element descriptor, whereinsaid panel GUI element descriptor defines an on-screen display thatincludes a plurality of elements, and wherein said panel GUI elementdescriptor further includes a focused identifier attribute thatindicates a pre-determined one of said plurality of elements as defaultfocus; and means for sending said panel GUI element descriptor to saidcontroller device such that said controller device displays saidon-screen display according to said panel GUI element descriptor andchooses said pre-determined element as focus.
 47. A target device asrecited in claim 46 wherein said on-screen display comprises anelectronic programming guide (EPG).
 48. A target device as recited inclaim 46 wherein said on-screen display comprises a pop-up menu.
 49. Atarget device as recited in claim 46 wherein said controller devicecomprises a digital television.
 50. A target device as recited in claim46 wherein said target device comprises a set-top box.
 51. In a systemhaving a controller device and a target device, a method for realizingcomplex graphical user interface (GUI) on said controller device, saidmethod comprising steps of: said controller device receiving a text GUIelement descriptor from said target device, wherein said text GUIelement descriptor defines a text element to be displayed and whereinsaid text GUI element descriptor further includes a font styleattribute; and said controller device displaying said text elementaccording to said font style attribute.
 52. A method as recited in claim51 wherein said font style attribute indicates that said text element isto be displayed in bold.
 53. A method as recited in claim 52 whereinsaid font style attribute indicates that said text element is to bedisplayed with underline.
 54. A method as recited in claim 53 whereinsaid font style attribute indicates that said text element is to bedisplayed with text color and background color reversed.
 55. Acontroller device configured for coupling to a target device via adigital bus, said controller device comprising: means for receiving atext GUI element descriptor from said target device, wherein said textGUI element descriptor defines a text element to be displayed andwherein said text GUI element descriptor further includes a font styleattribute; and means for displaying said text element according to saidfont style attribute.
 56. A controller device as recited in claim 55wherein said font style attribute indicates that said text element is tobe displayed in bold.
 57. A method as recited in claim 55 wherein saidfont style attribute indicates that said text element is to beunderlined when displayed.
 58. A method as recited in claim 55 whereinsaid font style attribute indicates that said text element is to bedisplayed with text color and background color reversed.
 59. A targetdevice configured for coupling to a controller device via a digital bus,said target device comprising: means for storing a text GUI elementdescriptor, wherein said text GUI element descriptor defines a textelement to be displayed and wherein said text GUI element descriptorfurther includes a font style attribute; and means for sending said textGUI element descriptor to said controller device such that saidcontroller device displays said text element according to said fontstyle attribute.
 60. A target device as recited in claim 59 wherein saidfont style attribute indicates that said text element is to be displayedin bold.
 61. A target device as recited in claim 59 wherein said fontstyle attribute indicates that said text element is to be underlinedwhen displayed.
 62. A target device as recited in claim 59 wherein saidfont style attribute indicates that said text element is to be displayedwith text color and background color reversed.